Gout is caused by a buildup in the body of uric acid, in the form of monosodium urate crystals that the body cannot rid itself of quickly. This condition is characterized by hyperuricemia, referring to an elevation in the serum level of uric acid. It is not fully understood why some people with hyperuricemia develop gout and others do not. Gout is characterized by recurrent attacks of painful, red, tender, warm, and swollen joints, which generally affects only one joint at a time, often the large toe. It is more common in men, but also affects women after menopause. Repeated flares of gout can lead to chronic gouty arthritis, with involvement of multiple joints and the development of subcutaneous nodules, called tophi.  While gout can be an intermittent condition, it can also lead to severe chronic arthritis and joint damage and deformity. Gout occurs frequently in patients with what is termed the metabolic syndrome and affects patients who also have diabetes, hypertension, and obesity.

Other crystal arthropathies can be caused by deposits of calcium pyrophosphate dihydrate (CPPD) crystals in the joints and have symptoms similar to gout. CPPD deposition disease is less common than gout, although radiographic chondrocalcinosis is common in older adults.

Prevalence of Gout

Prevalence estimates of gout vary for the US from 1% - 4%, depending on the data source and time frame. In 2005, an estimated 6.1 million adults reported having gout at some time, with 3.0 million affected each year.1 Estimates from the MEPS analyzed for the economic data section reported  3.1 million US adults had gout annually for the years 2008-2012, an annual prevalence rate of 1.3%.(Reference Table 8.13 PDF CSV and Table 8.24 PDF CSV) Additional studies report a higher prevalence of 3.9%, or 8.3 million adults in 2007-2008, using the NHANES as the basis of estimates.2^,3^,4 Another NHANES study from 2007-2010 reported a prevalence of 3.8%.5 Overall, it is believed the prevalence of gout is rising, with obesity and hypertension cited as contributors.2^,4 A study of hospitalization trends using the NIS from 1993-2011 supported this, showing hospitalizations with a diagnosis of rheumatoid arthritis declining over the study period while diagnosis of gout was reported as increasing.6

Prevalence of gout is higher in males than in females, 5.9% to 2.0%, respectively,4 or at a ratio of 3-4:1. The incidence of gout increases with age, and was shown in the MEPS to be higher in the following select socio-demographic groups: non-Hispanic whites (2.3 of 3.1 million); married/had a partner (1.9 million); any private insurance (2.0 million); those with any limitation in IADLs, ADLs, functioning, work, housework, school, vision, or hearing (1.7 million). (Reference Table 8.24 PDF CSV).

Healthcare Utilization

Hospitalization

More than 850,000 hospitalizations in 2013 had a diagnosis of gout, representing 2.9% of hospitals visits for any diagnoses, and accounting for 3.3% of all hospital charges billed. Gout is diagnosed along with joint pain and soft tissue disorders when multiple diagnoses are made (7% and 3.5% cross-diagnosis, respectively). At discharge, patients diagnosed with gout are more likely to be transferred to short-term or home health care than those with any diagnoses (45% vs 31%). (Reference Table 3A.3.1.0.1 PDF CSV; Table 3A.3.0.2 PDF CSV; Table 3A.3.1.1.1 PDF CSV; Table 3A.3.1.3.1 PDF CSV)

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Ambulatory Care Visits

Gout diagnoses were made in only 0.5% of ambulatory care visits for any diagnosis, accounting for 5.3 million ambulatory visits. Ambulatory visits were made more frequently by males (72%), those aged 65 years and older (50%), non-Hispanic whites (59%), and by those living in the Northeast (rate of 2.8/100 persons versus 2.1/100 for all regions). (Reference Table 3A.3.2.0.1 PDF CSV; Table 3A.3.2.0.2 PDF CSV; Table 3A.3.2.0.3 PDF CSV; and Table 3A.3.2.0.4 PDF CSV)

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Economic Burden

Estimates for gout, defined as ICD-9-CM 274, were generated from 2008-2012 MEPS data; analysis was limited to those years because the ICD-9-CM code for gout was suppressed in 2013 and 2014 MEPS data. Combining direct and indirect costs for gout, total average costs annually for the years 2008-2012 were $26 billion. Incremental costs could not be calculated due to a small sample size. (Reference Table 8.13 PDF CSV)

Direct Costs

Among all adults with gout, all-cause per person direct costs were $11,936. Those with any limitation in work, housework, or school activities had the highest all-cause per person direct costs ($16,843) whereas those age 18-44 years had the lowest ($5,934). Total all-cause direct costs were $36.6 million.  Direct costs attributable to gout were not reported because the relative standard errors for the estimates was greater than 30%. (Reference Table 8.13 PDF CSV and Table 8.24 PDF CSV)

Indirect Costs

The percentage working during the year among adults age 18-64 years was similar for those with (85%) and without gout (88%). Per person, those with gout earned $6,810 more than those without gout; thus, overall, those with gout had negative earnings losses (aggregate of -10.0 billion). Like direct costs, earnings losses attributable to gout were not reported because the estimates were unreliable, with a relative standard error greater than 30%. (Reference Table 8.13 PDF CSV).

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• 1. Lawrence RC, Felson DT, Helmick CG, et al for the National Arthritis Data Workgroup. Estimates of the prevalence of arthritis and other rheumatic conditions in the United States:  Part II. Arthritis & Rheumatism 2008;58(1):26-35.
• 2. a. b. Gadol N. Global burden of gout: prevalence and risk factors. https://www.medpagetoday.com/resource-center/Gout/Global-Burden/a/54489 . Accessed September 25, 2017.
• 3. Dalbeth N, Merriman TR, Stamp LK. Gout. Lancet 2016:355(10055);2039-2052.
• 4. a. b. c. Zhu Y, Pandya BJ, Choi HK. The National Health and Nutrition Examination Survey 2007-2008. Arth & Rheum 2011:63(10);3136-3141. Doi 10.1002/art.30520.
• 5. Lim SY, Lu N, Oza A, et al. Trends in gout and rheumatoid arthritis hospitalizations in the United States, 1993-2011. JAMA. 2016:315(21);2345-2346.
• 6. Roddy E, Choi H. Epidemiology of gout. Rheum Dis Clin North Am. 2014:40(2);155-175. Doi: 10.1016/j.rdc.2014.01.001.